A previously healthy 4-year, 6-month-old (4y6m) female was transferred to our hospital because of a one-week history of high fever (39·1 °C) accompanied by abdominal pain and skin rash. Symptoms started 7 days before, a physical examination revealed rash, superficial lymph nodes, conjunctival and pharyngeal congestion, chapped lips, strawberry tongue, and chest auscultation with rough breath sounds. She had no sick contacts, recent travel, or prior illicit drug use. Admission laboratory blood tests revealed the following: white blood cells, 9·3×10^9/L; red blood cell count, 4·53×10^12/L; hemoglobin, 124·0 g/L; platelet count, 268×10^9/L; neutrophils, 81·31%; and lymphocytes, 13·22%. Urine examination showed the following: white blood cells, 20/μl; white blood cell, 4/HPF; ketone, 2+; urine specific gravity, 1·020; erythrocyte sedimentation rate, 18 mm/h; and CRP, 73·6 mg/L. She was treated with acyclovir, cefotiam, and vitamin B6 but did not improve and developed maculopapular diffuse rush on the day following hospitalization (2nd day after the onset of fever). Then, she was given 7·5 g/day γ-globulin for 2 days, while the fever was still intermittent (39·3 °C). Therefore, she was transferred to our hospital for further evaluation.
On admission to our hospital, the laboratory findings were as follows: white blood cells, 15·7×10^9/L; red blood cell count, 3·64×10^12/L; hemoglobin, 101·0 g/L; platelet count, 268×10^9/L; neutrophils, 84·7%; lymphocytes, 9·2%; and neutrophil count, 13·3×10^9/L. No dilatation of coronary arteries was found. Neck ultrasonography showed enlarged lymph nodes on the right side of the neck. All other findings in the physical examination were unremarkable. The patient was diagnosed with KD and treated with γ-globulin 2 g/kg/day and aspirin 600 mg per day. The diffuse skin rash was diminished accompanied by periungual peeling of fingers (Figure 1). The peak of fever decreased on the 2nd day after admission, and the laboratory results are summarized in Table 1. On Day 3, the patient had a short and sudden loss of right vision with no cause that lasted for 20 min and self-recovered after the attack. Ophthalmology tests revealed unremarkable abnormalities in the fundus (see Figure 2), ophthalmic artery color Doppler and pupillary reaction. Although bilateral visual field examination of the patient demonstrated scattered blind spots, the confidence of the results was low considering the ability to understand based on the age of the patient (see Figure 2). However, the loss of right vision reappeared on the morning of Day 4 for 10 min, and examinations continued to show no abnormalities. Then, the vision loss was self-recovered again. The ophthalmologist and neurologist suggested visual-evoked potentials (VEPs), brain MRI+MRA and EEG, and neck color Doppler to explore the causes; all the imaging results demonstrated no abnormal findings, neurological diseases and carotid stenosis and optic neuritis were excluded. Salvia miltiorrhiza polyphenolate and tafluprost eye drops were given to the patient to improve circulation and reduce intraocular pressure. The loss of vision appeared 5 times intermittently over the next few days, and the longest loss lasted for 2 hours. The causes remained unknown. Consultation with a specialist occurred, and the possibility of conversion disorder was first considered; however, whether the vision loss was due to conversion disorder needed to be confirmed. On Day 8, there was an important finding that the patient’s mother told us: the patient could paint normally with the shadow of the left eye during the period of the transient loss of right vision (Figure 3). The “painting test” was performed again during vision loss, and the results were the same as before. Based on the clinical findings, examinations and mother’s description, the diagnosis of visual conversion disorder was made. In the next few days, the laboratory blood tests were measured again and are summarized in Table 1. The amount of aspirin was reduced to 75 mg per day. The loss of vision disappeared, and the fever was resolved.